The Chinese star has credited him with saving her marriage and helping resurrect her game after she lost her way following her 2011 French Open victory, when the distractions of sponsors and media affected her form.

Every day he would say, 'Believe in yourself, believe in yourself'. But if I was really doing something wrong, he would say. 'This is wrong, you have to change

Li Na

He has also been a steadying influence on the now composed 31-year-old, who used to struggle to control her emotions on court.

"You know, when like last year I said I want to be top three, nobody believed me," Li said. "At the beginning of this year, I said I want to win another grand slam title. Nobody believed.

"More important is I believed, he believed, my team believed."

As well as being a steadying influence, Rodriguez helped save Li from retiring last June after she became disillusioned with media criticism, convincing her it was worth playing on.

She said it was tough adapting to his style in the beginning, but she had no regrets about hiring him.

"When I started working with him, I realised he was more cool. He's not stressful. So I felt I need a coach like him," she said.

"Every day he would say, 'Believe in yourself, believe in yourself'. But if I was really doing something wrong, he would say. 'This is wrong, you have to change'.

"But the most important thing is, working with him for one-and-a-half, two years, he didn't tell me what to do. He would say, 'You have to play yourself. You have to know yourself what you should do."

She said she is also better placed to deal with the pressures and demands that come with winning one of the majors, with the experienced Rodriguez by her side.

"When I won the French Open, nobody told me what I should do and also I didn't have any experience. I didn't know how much my life would change but I think now it's different," she said.

"This is the second one, it's not the first one. Carlos has a lot of experience, for sure. He will give me some information."

This article appeared in the South China Morning Post print edition as Rodriguez 'helped me believe in myself'